Coordinating provider datasets from SAMHSA (x2+) to NPI/NPPES and PALS

Documenting Jan/Feb 2021 decisions and problems to solve for provider datasets.

For **data recency & updates/archives**:
-- Include two DATE fields per table: date_firstfind and date_lastfind
-- Our oldest date_firstfind is 2019-12-24, when @mariekers downloaded the 420 records initially provided by Code for Philly et al. in Feb/Mar 2020 data hackathon

For **data privacy**:
-- DB will upload only rows where archival_only = FALSE

没有指定文件、测试或入口点。首先定位 provider-dataset 和数据库文档，然后检查所述的日期字段和 archival_only 隐私规则；完成的标准是清楚记录 Jan/Feb 2021 的决策和未解决的问题。

由索引模型根据 Issue 内容生成。